diff options
Diffstat (limited to 'v5/apf_interpreter.c')
| -rw-r--r-- | v5/apf_interpreter.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/v5/apf_interpreter.c b/v5/apf_interpreter.c index 00576f8..dd3850a 100644 --- a/v5/apf_interpreter.c +++ b/v5/apf_interpreter.c @@ -257,6 +257,7 @@ typedef union { #define JLT_OPCODE 18 /* Compare less than and branch, e.g. "jlt R0,5,label" */ #define JSET_OPCODE 19 /* Compare any bits set and branch, e.g. "jset R0,5,label" */ #define JBSMATCH_OPCODE 20 /* Compare byte sequence [R=0 not] equal, e.g. "jbsne R0,2,label,0x1122" */ + /* NOTE: Only APFv6+ implements R=1 'jbseq' version */ #define EXT_OPCODE 21 /* Immediate value is one of *_EXT_OPCODE */ #define LDDW_OPCODE 22 /* Load 4 bytes from data address (register + signed imm): "lddw R0, [5+R1]" */ #define STDW_OPCODE 23 /* Store 4 bytes to data address (register + signed imm): "stdw R0, [5+R1]" */ @@ -800,16 +801,17 @@ static int do_apf_run(apf_context* ctx) { /* imm is jump target offset. */ /* REG is offset of packet bytes to compare. */ if (cmp_imm > 0xFFFF) return PASS_PACKET; + Boolean do_jump = !reg_num; /* pc < program_len < ram_len < 2GiB, thus pc + cmp_imm cannot wrap */ if (!IN_RAM_BOUNDS(ctx->pc + cmp_imm - 1)) return PASS_PACKET; ASSERT_IN_PACKET_BOUNDS(REG); const u32 last_packet_offs = REG + cmp_imm - 1; ASSERT_RETURN(last_packet_offs >= REG); ASSERT_IN_PACKET_BOUNDS(last_packet_offs); - if (memcmp(ctx->program + ctx->pc, ctx->packet + REG, cmp_imm)) - ctx->pc += imm; + do_jump ^= !memcmp(ctx->program + ctx->pc, ctx->packet + REG, cmp_imm); /* skip past comparison bytes */ ctx->pc += cmp_imm; + if (do_jump) ctx->pc += imm; break; } /* There is a difference in APFv4 and APFv6 arithmetic behaviour! */ |